Biology subjects

Reiskind, M. H.

Publications and source records attributed to Reiskind, M. H..

5 recordsLinked to original sources

bioRxiv2026

Fine-scale landscape genomics show asymmetric patterns of gene flow for the invasive mosquito Aedes albopictus

Mosquito-borne viruses like dengue, Zika, and chikungunya pose increasing health risks in the United States due to the expanding range of Aedes albopictus, a highly invasive mosquito species that now has a global distribution. Aedes albopictus thrive in artificial containers associated with anthropogenic land use, allowing populations to reach high numbers in urban and suburban environments. While the global spread of Ae. albopictus has been well-characterized, the effects of heterogeneous urban landscapes on dispersal and gene flow at fine spatial scales remain unclear. This study analyzed the genetic connectivity of Aedes albopictus populations collected in Wake County, North Carolina in 2018. We used single nucleotide polymorphisms SNP data from double-digest restriction-enzyme associated DNA sequencing (ddRADseq), and examined genetic connectivity through principal component analysis (PCA) and genetic network analysis. We then evaluated migration and source sink dynamics using a Bayesian approach for SNP data (BA3-SNP). We found little evidence of genetic clustering or isolated populations of Ae. albopictus in Wake County, suggesting high gene flow between sites. Migration analysis demonstrated asymmetric gene flow from rural to urban regions within Wake County, with greater gene flow occurring between and within urban regions. These findings suggest that Ae. albopictus populations demonstrate substantial gene flow within local metropolitan areas, with urban city centers serving as genetic sinks and surrounding suburban and rural regions serving as sources. This study highlights how heterogeneous landscapes shape mosquito population connectivity and migration at fine spatial scales, which is critical for informing vector control and public health intervention strategies.

genetics↗

bioRxiv2025

Socioeconomic predictors of knockdown resistance in Aedes albopictus (Diptera: Culicidae)

Knockdown resistance (kdr) in the mosquito Aedes albopictus (Skuse) jeopardizes the effectiveness of insecticidal control. This is a pressing issue given the expanding range of the species and its role as vector to harmful viruses. Effectively preventing the emergence of resistance or removing the conditions that positively select for kdr mutations requires us first to understand how these conditions arise. Here, we investigate the association between wealth and the frequency of kdr in Ae. albopictus populations in Raleigh, North Carolina, USA. We hypothesized that kdr frequency correlates with wealth, measured by total property value. We speculate that wealthier neighborhoods apply chemical insecticides more frequently, leading to higher kdr frequencies. We tested this hypothesis by sampling mosquito populations from 31 different residential blocks across the city and along a property value gradient. We found a high frequency of 39.0% for mutations at locus F1534S of the voltage-gated sodium channel gene (vgsc). Kdr mutations were found at 84% of the blocks we sampled. Our statistical analysis indicates strong evidence for an association between wealth and F1534S frequency. We discuss these and other findings, and what this means for suburban mosquito control going forward.

evolutionary biology↗

bioRxiv2025

Rapid spread of knockdown resistance allele frequencies in a suburban population of Aedes albopictus

Aedes albopictus is a major vector of arboviral diseases and is often targeted by pyrethroid-based mosquito control in residential areas. While knockdown resistance (kdr) mutations are well documented in Ae. aegypti, their emergence in Ae. albopictus has been less studied, particularly in suburban environments where insecticide application is often uncoordinated. Understanding the temporal and spatial dynamics of resistance evolution in this context is critical for preserving the effectiveness of public health interventions. We conducted longitudinal sampling of Ae. albopictus populations in Wake County, North Carolina, from 2016 to 2024. Using a novel allele-specific PCR melt curve assay, we genotyped 2,273 mosquitoes at the F1534S locus in the voltage-gated sodium channel gene. Resistance allele frequencies were calculated annually and mapped across the county for three key years--2016, 2018, and 2023-- representing the pre-emergence, initial detection, and widespread phases of resistance development. Selection and dominance were estimated using the Wright-Fisher Approximate Bayesian Computation algorithm for locus F1534S. The F1534S resistance allele was first detected in 2018 at a central, affluent neighborhood. By 2023, the allele had spread throughout the sampling region, with the highest frequencies near the site of first detection. Resistance allele frequency peaked at 0.36 in 2023, accompanied by an increase in heterozygous and homozygous resistance genotypes. Temporally sampled sites showed consistent trends in rising resistance, with all temporally-sampled locations harboring resistance genotypes by 2022. The resistance allele was found to be under high selection pressure and partially recessive in this population. Our findings reveal rapid emergence and spatial expansion of the F1534S kdr allele in Ae. albopictus populations in a suburban setting. The pattern of spread suggests strong local selection pressure, likely driven by residential pyrethroid use. These results highlight the need for proactive resistance monitoring and integrated management strategies that address private-sector contributions to insecticide selection pressure.

evolutionary biology↗

bioRxiv2025

Spatiotemporal variation in abundance and genetic structure across the urban-rural landscape gradient: Aedes albopictus (Skuse, 1894) (Diptera: Culicidae) in Wake County, NC

Since its invasion of the United States in the 1980s, Aedes albopictus (Skuse, 1894) has become a major pest and a significant public health threat in the Southeastern USA. Despite its importance, we know little about its population genetics at fine spatial scales. To remedy this lack of information, we analyzed Ae. albopictus spatial variation in mosquito abundance and genetic structure in an urban-rural landscape over two years (2016 and 2018) in Wake County, NC, USA. We used a reduced representation sequencing method to generate between 11,00 to 30,000 SNPs that were used for population genetic analyses. We found spatial variation in both the abundance, genetic diversity, and significant differences in genetic divergence among sites that varied between the two years. The year-to-year variation in the population genetic patterns at the within county scale suggests a dynamic system which requires extensive geographic, temporal, and genomic sampling to resolve. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=138 SRC="FIGDIR/small/659333v1_ufig1.gif" ALT="Figure 1"> View larger version (50K): org.highwire.dtl.DTLVardef@1158719org.highwire.dtl.DTLVardef@58ba77org.highwire.dtl.DTLVardef@139e303org.highwire.dtl.DTLVardef@166f334_HPS_FORMAT_FIGEXP M_FIG C_FIG

genetics↗

bioRxiv2022

Finding mutations in all the wrong places: Prevalence of knock-down resistance F1534S 1 mutations among Aedes albopictus (family: Culicidae, order: Diptera) in North Carolina

BackgroundKnock-down resistance (kdr) mutations in the voltage gated sodium channel gene of Aedes species mosquitoes are biomarkers for resistance to pyrethroid insecticides. In the United States, few studies have reported kdr mutations among Aedes albopictus (family: Culicidae, order: Diptera, Skuse, 1895) populations. In this study we sought to explore the potential for permethrin-impregnated uniforms worn by military servicemembers to drive kdr emergence. Methods and ResultsWe collected 538 Aedes albopictus mosquitoes, including 156 from 4 sites at Fort Bragg (exposed), North Carolina and 382 from 15 sites in Wake County (control), North Carolina to compare the prevalence of kdr mutations. Of those successfully sequenced, we identified 12 (3.0%) mosquitoes with kdr mutations, all of which were attributed to variants at position 1534 within domain 3. All mutations were found in mosquitoes collected at Wake County sites; no mutations were identified at Fort Bragg. There was a focus of mutations observed at the Wake County sites with approximately 92% (11 of 12) of the mosquitoes with the mutation coming from one site, where kdr mutations represented 24.4% (11 of 45) of all mosquitoes collected. ConclusionsOur study did not show any evidence that universal implementation of permethrin-impregnated uniforms drives the development of resistance. In contrast, we observed highly focal resistance in a suburban area of Raleigh, which may be attributable to peri-domestic mosquito control activities that involve area dispersal of pyrethroid insecticides. More robust surveillance is needed to monitor the emergence and spread of resistance. AUTHOR SUMMARYResistance to commonly employed insecticides among Aedes albopictus (family: Culicidae, order: Diptera, Skuse, 1895) mosquitoes poses as a substantial public health threat. In this study we sought to explore the potential for permethrin-impregnated uniforms worn by military servicemembers to drive emergence of resistance to pyrethroid insecticides by collecting and testing mosquitoes from both military and civilian sites. Overall, we did not identify mosquitoes harboring resistance at Ft. Bragg, but did find a focus of resistance in sub-urban Raleigh, which may be driven by commercial, peri-domestic mosquito control activities. These results suggest that resistance to pyrethroid insecticides may be more prevalent in the United States than previously known, but highly heterogenous. More robust surveillance is needed to monitor the emergence and spread of resistance.

ecology↗